Air conditioner, pump-down management method for air conditioner, program, and storage medium

Abstract

To provide an air conditioner set so as to permit only a permitted operator such as a specialist to execute pump-down, a pump-down management method for an air conditioner, a program, and a storage medium.SOLUTION: An air conditioner includes an indoor unit, an outdoor unit, a refrigerant piping and a control part. The refrigerant piping connects the indoor unit and the outdoor unit to make a combustible refrigerant flow to the inside thereof. The control part acquires input information for permission of pump-down for recovering the combustible refrigerant in the refrigerant piping to the outdoor unit, determines whether the pump-down is permitted or not on the basis of the input information, and sets the pump-down to be executable when determined that the pump-down is permitted.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to an air conditioner, a pump-down management method for an air conditioner, a program, and a storage medium. [Background technology]

[0002] If refrigerant gas leaks during removal or relocation of an air conditioner including an indoor unit and an outdoor unit, it may lead to environmental destruction and may reduce the operating efficiency of the air conditioner after relocation. Therefore, when carrying out the work, pump-down is performed, which is a process of recovering the refrigerant gas in the refrigerant piping to the outdoor unit. For example, as described in Patent Document 1, an air conditioner capable of performing pump-down is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-227664 A Summary of the Invention [Problem to be solved by the invention]

[0004] Pumping down is possible for conventional air conditioners, and in some countries, even people who are not professional contractors who perform work such as removing air conditioners can perform pumping down. However, when performed by amateurs or novice workers who lack professional skills and knowledge, mistakes and misjudgments often occur, and there is a risk of refrigerant leakage. When flammable refrigerants (i.e., refrigerants that have flammability), such as natural refrigerants or alternative fluorocarbons, are used in air conditioners, there is a risk of fire or explosion if the refrigerant leaks.

[0005] An object of the present disclosure is to provide an air conditioner, a pump-down management method for an air conditioner, a program, and a storage medium that set pump-down to be executable by authorized operators. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the present disclosure provides an air conditioner, an air conditioner pump-down management method, a program, and a storage medium.

[0007] An air conditioner according to one aspect of the present disclosure includes an indoor unit, an outdoor unit, a refrigerant pipe, and a control unit. The refrigerant pipe connects the indoor unit and the outdoor unit, and a flammable refrigerant flows inside the refrigerant pipe. The control unit acquires input information for permitting pump-down to recover the flammable refrigerant in the refrigerant pipe to the outdoor unit, determines whether pump-down is permitted based on the input information, and sets pump-down to be executable when it is determined that pump-down is permitted.

[0008] An air conditioner according to another aspect of the present disclosure includes an indoor unit, an outdoor unit, a refrigerant pipe, and a control unit. The refrigerant pipe connects the indoor unit and the outdoor unit, and a flammable refrigerant flows inside the refrigerant pipe. The control unit obtains a determination result as to whether or not input information for permission of pump-down to recover the flammable refrigerant in the refrigerant pipe to the outdoor unit matches authentication information uniquely corresponding to the air conditioner or an authorized operator, determines whether or not pump-down is permitted based on the determination result, and sets pump-down to be executable if it is determined that pump-down is permitted.

[0009] Also provided is a pump-down management method for an air conditioner according to another aspect of the present disclosure. The air conditioner includes an indoor unit, an outdoor unit, a refrigerant pipe, and a control unit. The refrigerant pipe connects the indoor unit and the outdoor unit, and a flammable refrigerant flows inside. The pump-down management method includes a step of acquiring input information for permission of pump-down to recover the flammable refrigerant in the refrigerant pipe to the outdoor unit, a step of determining whether or not pump-down is permitted based on the input information, and a step of setting pump-down to be executable when it is determined that pump-down is permitted.

[0010] Also provided is a pump-down management method for an air conditioner according to another aspect of the present disclosure. The air conditioner includes an indoor unit, an outdoor unit, a refrigerant pipe, and a control unit. The refrigerant pipe connects the indoor unit and the outdoor unit, and a flammable refrigerant flows inside. The pump-down management method includes the steps of: acquiring a determination result as to whether or not input information for permission of pump-down to recover flammable refrigerant in the refrigerant pipe to the outdoor unit matches authentication information uniquely corresponding to the air conditioner or an authorized operator; determining whether or not pump-down is authorized based on the determination result; and setting pump-down to be executable when it is determined that pump-down is authorized.

[0011] Moreover, a program according to another aspect of the present disclosure is a computer program for causing an air conditioner to execute the above-described pump-down management method.

[0012] A storage medium according to another aspect of the present disclosure is a non-transitory computer-readable storage medium having a computer program stored therein, the computer program implementing the above-described pump-down management method when executed by a processor. Effect of the Invention

[0013] According to the air conditioner, the pump-down management method for the air conditioner, the program, and the storage medium described in the present disclosure, it is possible to set pump-down to be executable by authorized operators. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a block diagram showing an example of a schematic configuration of an air conditioner according to a first embodiment. [Figure 2A] FIG. 1 is a diagram showing a refrigeration cycle of an air conditioner according to a first embodiment. [Figure 2B] FIG. 1 is a diagram showing a refrigeration cycle of an air conditioner according to a first embodiment. [Diagram 3] 1 is a flowchart illustrating an example of a pump-down management method for an air conditioner according to a first embodiment. [Figure 4A] FIG. 1 is a sequence diagram of an example of a pump-down management method for an air conditioner according to the first embodiment; [Figure 4B] FIG. 1 is a sequence diagram of an example of a pump-down management method for an air conditioner according to the first embodiment; [Diagram 5] 1 is a flowchart illustrating an example of step S200 according to the first embodiment. [Figure 6] 10 is a flowchart showing an example of a pump-down management method for an air conditioner according to a second embodiment. [Figure 7] 10 is a flowchart showing an example of a pump-down management method for an air conditioner according to a second embodiment. [Figure 8] 10 is a flowchart showing an example of a pump-down management method for an air conditioner according to a second embodiment. [Figure 9A] FIG. 13 is a schematic diagram of an example of a user interface (UI) when inputting authentication information in the second embodiment; [Figure 9B] FIG. 13 is a schematic diagram of an example of a UI when authentication is successful in the second embodiment; [Figure 9C] FIG. 13 is a schematic diagram of an example of a UI when authentication fails in the second embodiment; [Figure 10] 11 is a flowchart showing an example of a pump-down management method for an air conditioner according to a third embodiment. [Figure 11] FIG. 11 is a sequence diagram of an example of a pump-down management method for an air conditioner according to a third embodiment. [Figure 12] 11 is a flowchart showing an example of a pump-down management method for an air conditioner according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] 《Technical concept》 Before describing specific embodiments of an air conditioner, a pump-down management method for an air conditioner, a program, and a storage medium according to the present disclosure, the technical concept described in the present disclosure will be described using an example. In the present disclosure, the air conditioner includes an indoor unit, an outdoor unit, and a refrigerant pipe connecting the indoor unit and the outdoor unit and through which a flammable refrigerant flows. The air conditioner includes a liquid-side valve for performing pump-down to recover refrigerant gas in the refrigerant pipe to the outdoor unit based on an operation by an operator.

[0016] In order to close the liquid-side valve when performing pump-down, the air conditioner determines that pump-down has started when it detects that the liquid-side valve has been closed or that the protective cover covering the liquid-side valve has been opened. At that time, in order to increase the safety of pump-down, the air conditioner temporarily sets pump-down to be unexecutable. Then, the air conditioner acquires input information for permitting pump-down, input by a user via an input unit of the air conditioner or a terminal device communicatively connected to the air conditioner. The air conditioner determines whether pump-down is permitted or not based on the input information and authentication information not known to unauthorized operators. If it is determined that pump-down is permitted, the air conditioner sets pump-down to be executable. On the other hand, if it is determined that pump-down is not permitted, the air conditioner maintains the state in which pump-down is unexecutable.

[0017] An authorized worker is, for example, a professional contractor who performs construction work such as removing an air conditioner, or a worker who belongs to a licensed business company. In this way, the state in which pump-down cannot be performed is lifted for authorized workers such as professional contractors. This prevents unauthorized workers from performing pump-down, reduces the possibility of refrigerant leakage due to incorrect operation or incorrect judgment by unauthorized workers, and improves the safety of pump-down.

[0018] Each of the embodiments described below shows an example of the present disclosure. The numerical values, shapes, configurations, steps, and order of steps shown in each of the following embodiments show examples and do not limit the present disclosure. Among the components in the following embodiment 1, components that are not described in the independent claim showing the highest concept are described as optional components.

[0019] In each of the embodiments described below, there may be cases where modified examples are shown for specific elements, and other elements include appropriate combinations of any configuration, and the combined configurations provide the respective effects. In the embodiments, the respective modified configurations are combined to provide the respective effects of the respective modified configurations.

[0020] In the following detailed description, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as expressing or implying the relative importance or ranking of technical features. Features qualified as "first" and "second" expressly or imply the inclusion of one or more of that feature.

[0021] First Embodiment DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of an air conditioner, an air conditioner pump-down management method, a program, and a storage medium according to the present disclosure will be described in detail below with reference to the drawings as appropriate.

[0022] Fig. 1 is a block diagram showing an example of a schematic configuration of an air conditioner according to embodiment 1. Fig. 2A and Fig. 2B are diagrams showing a refrigeration cycle of the air conditioner according to embodiment 1, and the arrows above refrigerant piping 22 indicate the flow of flammable refrigerant during cooling operation.

[0023] In the embodiment of FIG. 1, the air conditioner 1 includes an indoor unit 10, an outdoor unit 12, a storage unit 14, and a control unit 16. The air conditioner 1 may include a communication unit 18 for communicating with an authentication server 50 and a terminal device 60. The air conditioner 1 may include an input unit 20 for receiving input from a user. The air conditioner 1 may include a display for displaying visual information to a user. The air conditioner 1 also includes a liquid side valve 24 and a gas side valve 26 for pumping down. The air conditioner 1 may include at least one sensor to perform its functions.

[0024] As described below, the air conditioner 1 may be connected to an authentication server 50 related to the air conditioner 1 via the Internet. The air conditioner 1 may be connected to a terminal device 60, which is a smartphone of a user of the air conditioner 1, via the Internet. The air conditioner 1 may be connected to the terminal device 60, which is a remote controller for the air conditioner 1, via infrared rays. The air conditioner 1 may also be connected directly or indirectly to an external information source 70 and acquire some of the information related to air conditioning control from the external information source 70.

[0025] Below, an overview of each component will be given.

[0026] <Air conditioner 1> The air conditioner 1 treats, for example, the interior space of a room in a home or office as a controlled space that is the target of air conditioning control. The air conditioner 1 includes an indoor unit 10 provided on a wall or ceiling of the controlled space, an outdoor unit 12 provided outdoors or in a central air-conditioned room other than the controlled space, and refrigerant piping 22 connecting the indoor unit 10 and the outdoor unit 12. A flammable refrigerant flows inside the refrigerant piping 22. The air conditioner 1 has, for example, a cooling function, a heating function, and / or an air cleaning function. The air conditioner 1 may further include a ventilation device capable of dehumidifying or humidifying the indoor air of the controlled space. These functions and operation modes can be freely combined (for example, a cooling and dehumidifying function, a cooling and ventilation mode, etc.).

[0027] <Indoor unit 10> The indoor unit 10 includes an indoor heat exchanger 102 and an indoor fan 104 that blows into the room the air that has exchanged heat with the indoor heat exchanger 102. The indoor unit 10 may further include sensors such as an indoor temperature sensor, an indoor humidity sensor, and a human presence sensor.

[0028] <Outdoor unit 12> The outdoor unit 12 includes an outdoor heat exchanger 122 and an outdoor fan 124 that blows the air after heat exchange to the outdoors. The outdoor unit 12 further includes a compressor 126 that compresses the refrigerant, an expansion valve 128 that decompresses the refrigerant, and a four-way valve 129 that switches the flow direction of the refrigerant. The compressor 126, the four-way valve 129, the outdoor heat exchanger 122, the expansion valve 128, and the indoor heat exchanger 102 are connected in order to the refrigerant piping 26. The outdoor unit 12 may further include sensors such as an outdoor temperature sensor and a solar radiation sensor.

[0029] In cooling or dehumidifying operation, the air conditioner 1 executes a refrigeration cycle in which the refrigerant flows from the compressor 126 through the four-way valve 129, the outdoor heat exchanger 122, the expansion valve 128, and the indoor heat exchanger 102 in this order, before returning to the compressor 126. In heating operation, the air conditioner 1 executes a refrigeration cycle in which the refrigerant flows from the compressor 126 through the four-way valve 129, the indoor heat exchanger 102, the expansion valve 128, and the outdoor heat exchanger 122 in this order, before returning to the compressor 126.

[0030] The memory unit 14, control unit 16, communication unit 18, and input unit 20 of the air conditioner 1 may each be provided in the indoor unit 10 or the outdoor unit 12. In one embodiment, the memory unit 14, control unit 16, and communication unit 18 that communicates with a terminal device 60 serving as a remote controller and an authentication server 50 are provided in the indoor unit 10. The input unit 20 or another communication unit 18 for acquiring input information for permitting pump-down is provided in the outdoor unit 12.

[0031] <Storage section 14> The storage unit 14 is a recording medium for recording various information and control programs, and may be a memory that functions as a work area for the control unit 16. The storage unit 14 is realized, for example, by a flash memory, a RAM (Random Access Memory), a ROM (Read Only Memory), other storage devices, or an appropriate combination of these.

[0032] The storage unit 14 stores information and thresholds for executing a pump-down management method, and can store standards and thresholds for air conditioning control. The storage unit 14 may also store information acquired from a sensor, the authentication server 50, the terminal device 60, or an external information source 70. This information can be read by the control unit 16 when the functions of the air conditioner 1 are executed.

[0033] The storage unit 14 may also store a computer program for causing the control unit 16 to execute the pump-down management method. The storage unit 14 may be a non-transitory computer-readable storage medium in which the computer program is stored.

[0034] <Control unit 16> The control unit 16 is a controller that controls at least some of the functions of the air conditioner 1. The control unit 16 includes a general-purpose processor such as a CPU, MPU, MCU, FPGA, DSP, or ASIC that executes a program to realize a predetermined function. The control unit 16 can realize various controls in the air conditioner 1 by calling and executing a control program stored in the storage unit 14. The control unit 16 can also cooperate with the storage unit 14 to read and write data stored in the storage unit 14. The control unit 16 is not limited to a controller that realizes a predetermined function through the cooperation of hardware and software, and may be a hardware circuit designed specifically to realize the predetermined function.

[0035] The control unit 16 can communicate with the authentication server 50 via the communication unit 18. For example, authentication (determination) as to whether or not the worker is authorized to perform pump-down is performed by the authentication server 50. In this case, the control unit 16 transmits information used for authentication to the authentication server 50 via the communication unit 18, and receives the determination result of the authentication server 50 from the authentication server 50. The control unit 16 can also receive various commands from the user (for example, a command to start the cooling operation of the air conditioner 1) from the terminal device 60 via the communication unit 18. The control unit 16 also manages whether or not to perform pump-down based on a pump-down management method described later.

[0036] <Communications Division 18> The communication unit 18 can also communicate with the authentication server 50, the user's terminal device 60, and the like, and can also transmit and receive Internet packets, for example. As described above, the control unit 16 may cooperate with the authentication server 50 and / or the terminal device 60 via the communication unit 18. The communication unit 18 may communicate between the authentication server 50, the air conditioner 1, and the terminal device 60 in accordance with standards such as Wi-Fi (registered trademark), IEEE802.2, IEEE802.3, 3G, and LTE, and transmit and receive data. The communication unit 18 may communicate via the Internet, as well as an intranet, an extranet, a LAN, ISDN, a VAN, a CATV communication network, a virtual private network, a telephone line network, a mobile communication network, a satellite communication network, or the like, infrared rays, Bluetooth (registered trademark), or RFID (registered trademark).

[0037] <Input section 20> The input unit 20 is a device for acquiring input information for permission to pump down, and an operator can input the input information to the air conditioner 1 via the input unit 20. The input unit 20 may include at least one of a button, a keyboard, a touch panel, an RFID reader, a QR Code (registered trademark) reader, a barcode reader, an IC card reader, a magnetic card scanner, and an optical scanner.

[0038] <Refrigerant piping 22, liquid side valve 24, and gas side valve 26> As described above, the refrigerant pipe 22 connects the indoor unit 10 and the outdoor unit 12, and a flammable refrigerant flows therethrough. The liquid side valve 24 and the gas side valve 26 are stop valves provided in the refrigerant pipe 22 to perform pump-down. The liquid side valve 24 and the gas side valve 26 are used in a fully open or fully closed state, and open and close the refrigerant pipe 22 in the air conditioner 1. In one embodiment, the liquid side valve 24 is a two-way valve, and the gas side valve 26 is a three-way valve. Note that the liquid side valve 24 and the gas side valve 26 may be flow rate control valves. In general, when pump-down is not being performed, the liquid side valve 24 is maintained in a fully open state. As shown in FIG. 2A, the liquid side valve 24 can be disposed between the outdoor heat exchanger 122 and the expansion valve 128.

[0039] The term "liquid side" in this disclosure refers to the side where the flammable refrigerant is in the liquid phase in the refrigeration cycle during cooling operation, i.e., the side where the expansion valve is located between the condenser and the evaporator. The term "gas side" in this disclosure refers to the side where the flammable refrigerant is in the gas phase in the refrigeration cycle during cooling operation, i.e., the side where the compressor is located between the condenser and the evaporator. More specifically, the liquid side valve 24 is provided between the expansion valve 128 and the outdoor heat exchanger 122 (FIG. 2A) or between the indoor heat exchanger 102 and the expansion valve 128 (FIG. 2B), and the gas side valve 26 is provided between the indoor heat exchanger 102 and the compressor 126. Thus, the refrigerant piping 26 sequentially connects the compressor 126, the four-way valve 129, the outdoor heat exchanger 122, the expansion valve 128, the liquid side valve 22, the indoor heat exchanger 102, and the gas side valve 26.

[0040] <Authentication Server 50> The authentication server 50 is a server for determining (authenticating) whether or not the current worker is an operator authorized for pump-down. For example, an associated application 62 for authentication is installed on a terminal device 60 such as the worker's smartphone, and the air conditioner 1 performs authentication via the associated application 62. In this case, the authentication server 50 is an application server that manages the associated application 62. Furthermore, the authentication server 50 may be a management server of a manufacturer of the air conditioner 1 for managing at least one air conditioner 1 or for collecting data.

[0041] <Terminal device 60> The terminal device 60 is a device related to the air conditioner 1. For example, the terminal device 60 may be a controller for the air conditioner 1, or may be a controller capable of simultaneously managing and controlling a plurality of types of home appliances. The terminal device 60 may also be an information terminal capable of performing data communication with the air conditioner 1, such as a smartphone, a mobile phone, a mobile phone, a tablet, a wearable device, or a computer incorporating a dedicated associated application 62. The terminal device 60 may also be a dedicated terminal or a general-purpose terminal for inputting input information for permitting pump-down into the air conditioner 1.

[0042] <External information source 70> The external information source 70 is an information source that provides information on services that are not directly related to the air conditioner 1, such as a list of authorized operators, weather information, and information on the air quality of a specific area. For example, if pump-down can be performed by those with a specific national qualification, public qualification, or private qualification, the external information source 70 may be a website or database that stores a list of the names, identification codes, certification codes, registration numbers, license numbers, or license numbers of those qualified. The authentication server 50 may transfer information acquired from the external information source 70 to the air conditioner 1 or the terminal device 60. The air conditioner 1 may directly connect to the external information source 70 and acquire part of the information on pump-down management from the external information source 70, or may indirectly connect to the external information source 70 via the authentication server 50 or the terminal device 60 to acquire related information.

[0043] A general procedure for pumping down will be described below with reference to FIG. 2A. When starting pumping down, first, the liquid side valve 24 is fully closed, thereby preventing the flammable refrigerant from flowing downstream of the liquid side valve 24. Next, the air conditioner 1 continues cooling operation for a certain period of time, and the flammable refrigerant on the indoor unit 10 side in the refrigerant piping 22 is moved to the outdoor unit 12 side and recovered. The certain period of time may be, for example, 3 minutes, 5 minutes, or 10 minutes. Next, the gas side valve 26 is fully closed, and then the cooling operation is stopped. This completes the pumping down operation, the flammable refrigerant is recovered to the outdoor unit 12 side, and the indoor unit 10 and the outdoor unit 12 can be removed. Note that when pumping down, the liquid side valve 24 may be closed after the cooling operation.

[0044] Up to this point, we have provided an overview of the configuration, operation, and pump-down procedure of the air conditioner 1 according to this embodiment. From here on, we will explain the features of the pump-down management method, program, and storage medium used in the air conditioner 1 according to this embodiment.

[0045] <Pump down management method> The air conditioner 1 executes a pump-down management method. Figure 3 is a flowchart of an example of a pump-down management method for the air conditioner according to embodiment 1, and the pump-down management method includes steps S100 to S300.

[0046] In the pump-down management method, first, the control unit 16 acquires input information for permitting pump-down via the communication unit 18 or the input unit 20 (step S100). The input information may be a character string including at least one of letters, numbers, and symbols, or may be a numeric string including only numbers.

[0047] In one embodiment, the control unit 16 receives input information directly from the terminal device 60 via the communication unit 18. In one embodiment, the control unit 16 receives input information indirectly from the terminal device 60 via the authentication server 50 via the communication unit 18. In one embodiment, the control unit 16 receives input information directly from a user via the input unit 20. For example, the input unit 20 includes an RFID reader, and the worker has a card with an RFID inside which the input information is written. In this case, when the worker brings the card close to the input unit 20, the input unit 20 automatically reads the input information held by the card, thereby acquiring the input information.

[0048] The control unit 16 determines whether or not pump-down is permitted based on the input information (step S200). If it is determined that pump-down is permitted, the control unit 16 sets pump-down to be executable (step S300).

[0049] In one embodiment, the authentication information includes first authentication information that uniquely corresponds to the air conditioner 1. The first authentication information may be a character string including at least one of letters, numbers, and symbols, or may be a numeric string including only numbers. The first authentication information is a unique identification code, authentication code, or password assigned to the air conditioner 1. The first authentication information can be issued by the manufacturer / seller of the air conditioner 1, or an entity involved in the construction of the air conditioner 1. The pump-down worker can obtain permission and the first authentication information, for example, by contacting the issuer of the first authentication information (for example, a call center of the manufacturer / seller of the air conditioner 1).

[0050] The memory unit 12 of the air conditioner 1 stores the first authentication information. If the input information matches the first authentication information, the control unit 16 determines that pump-down is permitted, and on the other hand, if the input information does not match the first authentication information, it determines that pump-down is not permitted.

[0051] 4A is a sequence diagram of an example of a pump-down management method for an air conditioner in this embodiment. The air conditioner 1 acquires input information that has been directly input to the input unit 20 or transmitted from the terminal device 60, and performs a match determination between the input information and the first authentication information. In other words, both the acquisition of the input information and the match determination are performed by the air conditioner 1. When the input information is acquired directly from the input unit 20 or the terminal device 60, authentication can be performed in step S200 without going through the Internet.

[0052] FIG. 4B is a sequence diagram of an example of a pump-down management method for an air conditioner in another embodiment, and FIG. 5 is a flowchart of an example of step S200 corresponding to FIG. 4B.

[0053] 4B and 5, the input information is acquired by the air conditioner 1, but the matching determination is performed by the authentication server 50. In this embodiment, the authentication information may include first authentication information or may include second authentication information uniquely corresponding to an authorized worker. The first authentication information or the second authentication information is stored in the authentication server 50.

[0054] The second authentication information may be a character string including at least one of letters, numbers, and symbols, or may be a numeric string including only numbers. The second authentication information is a unique identification code, certification code, registration number, license number, or permit number given to an authorized worker. The second authentication information can be issued by an entity that certifies qualifications related to pump-down authorization, an entity related to the construction of the air conditioner 1, a manufacturer / seller of the air conditioner 1, or the like.

[0055] The control unit 16 transmits the acquired input information to the authentication server 50 via the communication unit 18 so that the authentication server 50 makes a match determination (step S210). When the authentication server 50 receives the input information and the request for match determination, it determines whether the input information matches the stored first authentication information or second authentication information, and transmits the determination result to the air conditioner 1. The control unit 16 then receives the determination result from the authentication server 50 via the communication unit 18 (step S220), and determines whether pump-down is permitted based on the determination result (step S230). For example, if the determination result indicates that the input information matches the first authentication information, the control unit 16 determines that pump-down is permitted. On the other hand, if the determination result indicates that the input information does not match the first authentication information, it determines that pump-down is not permitted.

[0056] If it is determined that pump-down is permitted, the control unit 16 sets pump-down to be executable. For example, the control unit 16 sets pump-down to be executable by maintaining the liquid-side valve 24, the gas-side valve 26, and the compressor 126 in an operable state. Note that, if pump-down has been set to be infeasible, in step S300, the control unit 16 cancels the state in which pump-down is infeasible.

[0057] 3, if it is determined that pump-down is not permitted, the controller 16 terminates the pump-down management method. In another embodiment, if it is determined that pump-down is not permitted, the controller 16 sets pump-down as not executable.

[0058] In one embodiment, before step S100, the control unit 16 presents a UI for prompting the input of input information. For example, the air conditioner 1 further includes a human presence sensor provided near the liquid-side valve 24 and a display for displaying the UI. When the human presence sensor detects that an operator has approached the liquid-side valve 24, the control unit 16 causes the display to display a UI for prompting the input of input information.

[0059] By executing step S300 or by setting pump-down as infeasible, processing of the pump-down management method is completed. After pump-down is set as infeasible, an authorized operator can perform pump-down according to the procedure described above.

[0060] According to the air conditioner 1 and pump-down management method described above, pump-down can be set to be executable by authorized workers such as specialists, thereby improving the safety of pump-down. It is possible to determine whether pump-down is permitted or not by comparing the input information with the first authentication information or the second authentication information that is unknown to unauthorized workers. Furthermore, the match determination can be made not only by the air conditioner 1, but also by the authentication server 50.

[0061] In one embodiment, the air conditioner 1 comprises a program used to execute the pump-down management method described above. The program causes the air conditioner 1 to execute the pump-down management method.

[0062] Second Embodiment <Limit pump down before authentication> In the second embodiment, when it is determined that there is a possibility that a pump-down will be initiated, the air conditioner temporarily sets pump-down to be unexecutable. In this way, the risk of an operator executing pump-down without authentication can be avoided, and the safety of pump-down can be improved.

[0063] Fig. 6 is a flowchart of an example of a pump-down management method for an air conditioner according to embodiment 2, and the pump-down management method includes steps S100 to S500. Steps S100 to S300 in Fig. 6 are the same as steps S100 to S300 in Fig. 3, and detailed description will be omitted here.

[0064] As described above, when performing pump-down, the liquid side valve 24 needs to be closed, so when the air conditioner 1 detects that the liquid side valve 24 is closed, it determines that pump-down has begun.

[0065] In one embodiment, the air conditioner 1 includes a proximity sensor or other sensor capable of detecting the opening and closing of the liquid-side valve 24. The control unit 16 can determine whether the liquid-side valve 24 is closed or not based on the output of the sensor.

[0066] In one embodiment, the air conditioner 1 further includes a refrigerant pressure sensor 28 that detects the refrigerant pressure of the flammable refrigerant flowing through the refrigerant piping 22. As shown in FIG. 2A, the refrigerant pressure sensor 28 is provided between the expansion valve 128 and the liquid side valve 24 in the refrigerant piping 22, and the pressure sensor 28 is disposed downstream of the liquid side valve 24. When the cooling operation is performed with the liquid side valve 24 closed, the flammable refrigerant does not flow into the refrigerant piping 22 downstream of the liquid side valve 24. On the other hand, the gaseous flammable refrigerant is sucked into the compressor 126 and accumulates inside the outdoor unit 12, and the liquid flammable refrigerant accumulates in the outdoor heat exchanger 122 as a condenser and in a receiver (not shown) downstream of the refrigerant piping 22. Therefore, in the refrigeration cycle shown in FIG. 2A, the amount of flammable refrigerant downstream of the liquid side valve 24 is reduced compared to the case of cooling operation with the liquid side valve 24 open, and the detection value of the refrigerant pressure sensor 28 is lower. When the control unit 16 determines that the refrigerant pressure detected by the refrigerant pressure sensor 28 is lower than a predetermined refrigerant pressure threshold value, it determines that the liquid side valve 24 is closed.

[0067] In one embodiment, the air conditioner 1 includes a first refrigerant pressure sensor 28A and a second refrigerant pressure sensor 28B that detect the refrigerant pressure of the flammable refrigerant flowing through the refrigerant pipe 22. FIG. 2B is a diagram showing a refrigeration cycle of this embodiment. Compared to the refrigeration cycle of FIG. 2A, the installation positions of the liquid side valve 24, the first refrigerant pressure sensor 28A, and the second refrigerant pressure sensor 28B are different. The first refrigerant pressure sensor 28A is provided between the expansion valve 128 and the liquid side valve 24 in the refrigerant pipe 22. The second refrigerant pressure sensor 28B is provided between the liquid side valve 24 and the indoor heat exchanger 102 in the refrigerant pipe 22. When the liquid side valve 24 is open, there is almost no pressure difference between the refrigerant pressure detected by the first refrigerant pressure sensor 28A and the refrigerant pressure detected by the second refrigerant pressure sensor 28B, that is, there is almost no pressure difference between the upstream and downstream of the liquid side valve 24. When cooling operation is performed with the liquid side valve 24 closed, the amount of flammable refrigerant downstream of the liquid side valve 24 decreases more than the amount of flammable refrigerant upstream of the liquid side valve 24. Therefore, the refrigerant pressure detected by the second refrigerant pressure sensor 28B becomes lower than the refrigerant pressure detected by the first refrigerant pressure sensor 28A, and a pressure difference occurs upstream and downstream of the liquid side valve 24. The control unit 16 determines whether the liquid side valve 24 is open or closed based on the pressure difference upstream and downstream of the liquid side valve 24. For example, when the control unit 16 determines that the absolute value of the pressure difference is greater than a predetermined pressure difference threshold, it determines that the liquid side valve 24 is closed.

[0068] In one embodiment, the air conditioner 1 further includes a protective cover 30 that covers the liquid side valve 24, and an opening / closing sensor 32 that detects whether the protective cover 30 is open or closed. The opening / closing sensor 32 is, for example, a contact sensor or a proximity sensor. Since the liquid side valve 24 is covered by the protective cover 30, it is necessary to open the protective cover 30 or to open and then remove it before operating the liquid side valve 24 to open or close it. In addition, generally, when pump-down is not being performed, the liquid side valve 24 is maintained in a fully open state. If the opening / closing sensor 32 detects that the protective cover 30 that covers the liquid side valve 24 has been opened, it is considered that someone is trying to close the liquid side valve 24, that is, to perform pump-down. Therefore, when the opening / closing sensor 32 detects that the protective cover 30 is open, the air conditioner 1 determines that pump-down has started.

[0069] In other words, the control unit 16 monitors whether or not the liquid side valve 24 has been closed or the protective cover 30 has been opened (step S400), and if the control unit 16 detects that the liquid side valve 24 has been closed or the protective cover 30 has been opened, it restricts the execution of pump-down by setting the pump-down to be unexecutable (step S500).

[0070] After once setting pump-down as infeasible, the control unit 16 acquires input information for permitting pump-down (step S100) and attempts to authenticate the operator (step S200). If it is determined that pump-down is permitted for the operator, the control unit 16 sets pump-down as executable so as to remove the restriction on pump-down (step S300). That is, if the control unit 16 detects that the liquid-side valve 24 is closed or the protective cover 30 is open, it sets pump-down as infeasible until it is determined that pump-down is permitted.

[0071] On the other hand, when it is determined that pump-down is not permitted, the control unit 16 does not remove the restriction on pump-down, and causes the air conditioner 1 to maintain a state in which pump-down cannot be performed.

[0072] As one of the means for restricting pump-down, the control unit 16 can set pump-down to be unexecutable by maintaining the compressor 126 in a stopped state. In pump-down, it is necessary to recover flammable refrigerant by operating the compressor 126 in cooling mode. Therefore, if the compressor 126 is maintained in a stopped state, pump-down cannot be executed. Also, when the compressor 126 is operating, the control unit 16 stops the compressor 126 and maintains it in the stopped state.

[0073] As another means for restricting pump-down, the control unit 16 can set pump-down to be disabled by maintaining the liquid-side valve 24 in an open state. Since pump-down is performed with the liquid-side valve 24 closed, maintaining the liquid-side valve 24 in an open state makes it impossible to perform pump-down. Also, if the liquid-side valve 24 is already closed, the control unit 16 opens the liquid-side valve 24 and maintains it in a stopped state.

[0074] This completes the process of managing whether pump-down can be performed. The control unit 16 can detect that pump-down has started by detecting that the liquid-side valve 24 is closed or the protective cover 30 is open. Then, by temporarily setting pump-down as unexecutable until it is determined that pump-down is permitted, it is possible to prevent unauthorized workers from performing pump-down. Furthermore, by maintaining the compressor 126 in a stopped state or maintaining the liquid-side valve 24 in an open state, it is possible to effectively limit pump-down, thereby improving the safety of pump-down.

[0075] Further embodiments of the pump-down management method and available UI are described below.

[0076] <Limit the time when pump down can be performed> In this embodiment, when the control unit 16 sets pump-down as executable, it also sets the executable time, thereby making it possible to further increase the safety of pump-down.

[0077] Fig. 7 is a flowchart of an example of a pump-down management method for an air conditioner, and the pump-down management method includes steps S100 to S700. Steps S100 to S500 in Fig. 7 are the same as steps S100 to S500 in Fig. 6, and detailed description will be omitted here.

[0078] In the embodiment shown in FIG. 7, the control unit 16 sets pump-down as executable (step 300), and then further sets an executable time during which pump-down is executable (step S600). For example, the control unit 16 sets a timer for the executable time, and maintains the pump-down executable state until the executable time has elapsed. After setting the executable time, the control unit 16 monitors whether the executable time has elapsed (step S700). If it is determined that the executable time has elapsed, the control unit 16 again sets pump-down as inexecutable (step S800), and then completes the management.

[0079] The permitted worker performs pump-down during the executable time, and then proceeds with the work of removing or relocating the air conditioner 1. In some cases, the worker may perform pump-down again until the work of removing or relocating the air conditioner 1 is completed. Therefore, the executable time may be set taking into consideration the time required for pump-down, or may be set taking into consideration the time required for the entire work. For example, the control unit 16 may set the executable time to 30 minutes, 1 hour, 3 hours, 6 hours, 12 hours, 24 hours, 36 hours, or 48 hours.

[0080] By setting the executable time in this manner, even if pump-down is permitted, it is possible to execute pump-down within a certain period of time, thereby further improving the safety of pump-down.

[0081] <Notifications and warnings during restrictions> In this embodiment, the control unit 16 provides notifications and warnings to the operator regarding pump down limitations.

[0082] Fig. 8 is a flowchart of an example of a pump-down management method for an air conditioner, and the pump-down management method includes steps S100 to S500 and step S900. Steps S100 to S500 in Fig. 8 are the same as steps S100 to S500 in Fig. 6, and detailed description will be omitted here.

[0083] If it is determined that pump-down is not permitted (after step S500), or if pump-down is set to be unexecutable (after step S200), the control unit 16 outputs information that pump-down is unexecutable (step S800). More specifically, the control unit 16 causes the air conditioner 1 or the terminal device 60 to output information indicating that pump-down is unexecutable.

[0084] The information indicating that pump-down cannot be performed includes, for example, at least one of characters, symbols, sounds, and images indicating the content "pump-down cannot be performed." The control unit 16 may output information indicating that the worker is unauthenticated or that the worker is not permitted to pump-down. The control unit 16 causes such information to be displayed on the display of the air conditioner 1 or the terminal device 60, or to be spoken through a speaker. Alternatively, the control unit 16 may cause the air conditioner 1 to sound a warning alarm at a high volume.

[0085] Such a notice or warning may be presented to an operator to communicate that authorization is required for pump down and may also serve to warn unauthorized operators.

[0086] Fig. 9A is a schematic diagram of an example of a UI when inputting authentication information in the second embodiment. Before step S100, as shown in Fig. 9A, the control unit 16 causes the air conditioner 1 or the terminal device 60 to display a UI for prompting input of input information. In this embodiment, the authentication information is an authentication number uniquely assigned to an authorized operator, and is stored in the authentication server 50. On the screen SC1 of Fig. 9A, characters prompting input of the authentication number, and a text box and button for receiving the input information are displayed. In addition, a message stating "Only authorized operators can perform pump down" is also displayed.

[0087] When the worker inputs the authentication number, the control unit 16 executes the above-mentioned steps S100 to S900. The control unit 16 uses the input authentication number as input information, and determines whether or not the worker is permitted to perform pump-down based on the input information, and sets pump-down as executable or inexecutable.

[0088] FIG. 9B is a schematic diagram of an example of a UI when authentication is successful, and FIG. 9C is a schematic diagram of an example of a UI when authentication is unsuccessful.

[0089] If it is determined in step S200 that pump-down is permitted, that is, if authentication of the worker is successful, the control unit 16 sets pump-down to be executable in step S300, and sets the executable time in step S600. As shown on screen SC2 in Fig. 9B, the control unit 16 causes the air conditioner 1 or terminal device 60 to display that pump-down is executable and the deadline for executable. This allows the worker to easily know until when pump-down or work related to the air conditioner 1 has to be completed.

[0090] On the other hand, if it is determined in step S200 that pump-down is not permitted, that is, if authentication of the operator has failed, the control unit 16 maintains the state in which pump-down cannot be performed, and outputs information indicating that it cannot be performed in step S900. As shown in screen SC3 in FIG. 9C, the control unit 16 causes the air conditioner 1 or the terminal device 60 to display an image showing a warning and messages such as "You are not an authorized operator" and "Pump-down cannot be performed." This allows the operator to understand the situation in which restrictions are imposed because permission for pump-down has not been obtained, and the operator is not confused even if he or she is unable to close the liquid-side valve 24 or start cooling operation.

[0091] Third Embodiment <Determining permission without obtaining input information> In the third embodiment, the air conditioner 1 can cooperate with the authentication server 50 to determine whether or not an operator is authorized and to manage pump-down, without acquiring input information.

[0092] Fig. 10 is a flowchart of an example of an air conditioner pump-down management method according to embodiment 3, and the air conditioner pump-down management method includes steps S1010 to S1030. Fig. 11 is a sequence diagram of the air conditioner pump-down management method shown in Fig. 10.

[0093] As shown in Fig. 11, in the third embodiment, input information is input by a terminal device 60 and transmitted to an authentication server 50. The authentication server 50 compares the received input information with authentication information stored in the authentication server 50 to determine whether the input information matches the authentication information. The authentication server 50 then transmits determination information to the air conditioner 1. Note that the authentication information may include at least one of the first authentication information and second authentication information described above, that is, it includes information uniquely corresponding to the air conditioner 1 or an authorized operator.

[0094] The control unit 16 acquires a determination result as to whether or not the input information matches the authentication information from the authentication server 50 via the communication unit 18 (step S1010). The control unit 16 determines whether or not pump-down is permitted based on the acquired determination result (step S1020), and if it is determined that pump-down is permitted, sets pump-down to be executable (step S1030). For example, if the determination result indicates that the input information matches the authentication information, the control unit 16 determines that pump-down is permitted. On the other hand, if the determination result indicates that the input information does not match the authentication information, it determines that pump-down is not permitted.

[0095] As in the first and second embodiments, when the control unit 16 determines that pump-down is not permitted, it can set pump-down as not executable. Also, as in the first and second embodiments, when the control unit 16 determines that pump-down has started, it can temporarily set pump-down as not executable. Also, as in the first and second embodiments, the control unit 16 can set an executable time and output a notification of the executable time or the impossibility of execution.

[0096] Fig. 12 is a flowchart of an example of a pump-down management method for an air conditioner according to embodiment 3. Steps S1030 to S1050 in Fig. 12 are the same as steps S300 to S500 in Fig. 6. When control unit 16 detects that liquid-side valve 24 is closed or protective cover 30 is open (step S1040), it sets pump-down to be unexecutable (step S1050). Control unit 16 then waits for the result of the determination by authentication server 50, and based on the received result of the determination, sets pump-down to be executable or maintains that pump-down is unexecutable (steps S1010 to S1030).

[0097] This completes the process of managing pump-down based on the determination result of authentication server 50. In the third embodiment, acquisition of input information and match determination are performed without going through the air conditioner 1. Even in this case, the air conditioner 1 can determine whether pump-down is permitted and manage whether pump-down can be performed, thereby improving the safety of pump-down.

[0098] (Other embodiments) (Additional Note) The above description of the embodiments discloses the following techniques.

[0099] (Technology 1) An air conditioner including an indoor unit, an outdoor unit, refrigerant piping connecting the indoor unit and the outdoor unit and through which a flammable refrigerant flows, and a control unit, wherein the control unit obtains input information for permitting pump-down to recover the flammable refrigerant in the refrigerant piping to the outdoor unit, determines whether pump-down is permitted based on the input information, and if it determines that pump-down is permitted, sets pump-down to be executable.

[0100] This configuration allows pump-down to be set so that only authorized personnel, such as specialists, can perform pump-down, thereby improving the safety of pump-down.

[0101] (Technology 2) The air conditioner further includes a liquid side valve provided in the refrigerant piping to control the flow of the flammable refrigerant, and when the control unit detects that the liquid side valve is closed, it sets pump down to be unable to be performed until it determines that pump down is permitted. This is the air conditioner described in Technology 1.

[0102] Since pump-down requires closing the liquid-side valve, it is possible to detect that pump-down has started by detecting that the liquid-side valve is closed. By setting pump-down as unexecutable until it is determined that pump-down is permitted, it is possible to prevent unauthorized operators from performing pump-down.

[0103] (Technology 3) The outdoor unit includes an expansion valve provided in the refrigerant piping, and the air conditioner further includes a refrigerant pressure sensor that is provided in the refrigerant piping between the expansion valve and the liquid side valve and detects the refrigerant pressure of the flammable refrigerant flowing through the refrigerant piping, and the control unit determines whether to open or close the liquid side valve based on the refrigerant pressure detected by the refrigerant pressure sensor. This is the air conditioner described in Technology 2.

[0104] The refrigerant pressure sensor can accurately detect whether the liquid side valve is closed. If it is detected that the refrigerant in the refrigerant pipe is decreasing, it can be determined that pump-down has started.

[0105] (Technology 4) The indoor unit includes an indoor heat exchanger, the outdoor unit includes an expansion valve provided in the refrigerant piping, and the air conditioner further includes a first refrigerant pressure sensor and a second refrigerant pressure sensor that detect a refrigerant pressure of the flammable refrigerant flowing through the refrigerant piping. The first refrigerant pressure sensor is provided in the refrigerant piping between the expansion valve and the liquid-side valve, and the second refrigerant pressure sensor is provided in the refrigerant piping between the liquid-side valve and the indoor heat exchanger. The control unit determines whether to open or close the liquid-side valve based on a pressure difference between the refrigerant pressure detected by the first refrigerant pressure sensor and the refrigerant pressure detected by the second refrigerant pressure sensor.

[0106] The first refrigerant pressure sensor and the second refrigerant pressure sensor can accurately detect whether the liquid side valve is closed. When it is detected that the refrigerant in the refrigerant pipe is decreasing, it can be determined that pump-down has started.

[0107] (Technology 5) The air conditioner described in any one of Technologies 1 to 4, further including a liquid side valve provided in the refrigerant piping for controlling the flow of the flammable refrigerant, a protective cover covering the liquid side valve, and an opening / closing sensor for detecting the opening / closing of the protective cover, wherein when the opening / closing sensor detects that the protective cover is open, the control unit sets pump down to be unable to be performed until it is determined that pump down is permitted.

[0108] By detecting that the protective cover covering the liquid side valve is open, it is possible to detect the possibility that a pump-down will be started. Then, by setting pump-down to be inoperative until it is determined that pump-down is permitted, it is possible to prevent unauthorized operators from performing pump-down.

[0109] (Technology 6) The air conditioner described in any one of Technologies 1 to 5, wherein the outdoor unit further includes a compressor connected to the refrigerant piping, and the control unit sets pump-down to be unexecutable by maintaining the compressor in a stopped state.

[0110] Since cooling operation is required during pump-down, if the compressor is kept stopped, cooling operation is not possible and pump-down cannot be performed. By setting in this way, it is possible to prevent unauthorized workers from performing pump-down.

[0111] (Technology 7) The air conditioner according to claim 1 or 5, wherein the control unit sets pump-down to be unexecutable by maintaining the liquid-side valve in an open state.

[0112] Since the liquid side valve needs to be closed during pump-down, pump-down cannot be performed if the liquid side valve is kept open. By setting it in this way, it is possible to prevent unauthorized personnel from performing pump-down.

[0113] (Technology 8) The air conditioner according to any one of Techniques 1 to 7, wherein, when it is determined that pump-down is permitted, the control unit sets an executable time during which pump-down can be performed.

[0114] By setting an executable time, even if pump-down is permitted, it can be performed only within a certain time period, thereby further improving the safety of pump-down.

[0115] (Technology 9) An air conditioner described in any one of Technologies 1 to 8, wherein if the control unit determines that pump down is not permitted or sets pump down as not executable, information indicating that pump down cannot be performed is output to the air conditioner or a terminal device associated with the air conditioner.

[0116] This configuration allows a notification to be sent to an operator attempting to perform a pump-down that pump-down has been set as not executable, and this notification can convey that permission is required for pump-down, and can also convey a warning to unauthorized operators.

[0117] (Technology 10) The air conditioner described in any one of Technologies 1 to 9, further including an input unit or communication unit that acquires the input information, and a memory unit that stores first authentication information uniquely corresponding to the air conditioner, and when the control unit determines that the input information matches the first authentication information, it determines that pump down is permitted.

[0118] By comparing the input information with first authentication information that uniquely corresponds to the air conditioner, it is possible to determine whether or not pump-down is permitted.

[0119] (Technology 11) The air conditioner further includes a communication unit, and the control unit acquires the input information via the communication unit or an input unit of the air conditioner, transmits the input information to an authentication server via the communication unit, receives a judgment result from the authentication server via the communication unit as to whether the input information matches second authentication information uniquely corresponding to an authorized worker, and determines whether pump down is permitted based on the judgment result.An air conditioner described in any one of Technologies 1 to 9.

[0120] A comparison of the input information with second authentication information that uniquely corresponds to an authorized operator can determine whether pump down is authorized.

[0121] (Technology 12) An air conditioner including an indoor unit, an outdoor unit, refrigerant piping connecting the indoor unit and the outdoor unit and through which a flammable refrigerant flows, and a control unit, wherein the control unit obtains a judgment result as to whether input information for permitting pump-down to recover the flammable refrigerant in the refrigerant piping to the outdoor unit matches authentication information uniquely corresponding to the air conditioner or an authorized operator, determines whether pump-down is permitted based on the judgment result, and sets pump-down to be executable if it is determined that pump-down is permitted.

[0122] With this configuration, pump-down can be set so that only authorized workers, such as specialists, can perform it, thereby improving the safety of pump-down. The air conditioner makes a permission decision based on input information entered into the air conditioner and can set whether or not to perform it. Furthermore, the air conditioner can receive a decision result from an authentication server or an information terminal of the worker, and can set whether or not to perform it based on the received decision result.

[0123] (Technology 13) A pump-down management method for an air conditioner, the air conditioner including an indoor unit, an outdoor unit, and refrigerant piping connecting the indoor unit and the outdoor unit and through which a flammable refrigerant flows, the pump-down management method including the steps of acquiring input information for permitting pump-down to recover the flammable refrigerant in the refrigerant piping to the outdoor unit, determining whether or not pump-down is permitted based on the input information, and setting pump-down to be executable if it is determined that pump-down is permitted.

[0124] According to this method, pump-down can be set so that only authorized workers, such as specialists, can perform pump-down, thereby improving the safety of pump-down.

[0125] (Technology 14) A pump-down management method for an air conditioner, the air conditioner including an indoor unit, an outdoor unit, and refrigerant piping connecting the indoor unit and the outdoor unit and through which a flammable refrigerant flows, the pump-down management method including the steps of: obtaining a determination result as to whether input information for authorizing pump-down to recover the flammable refrigerant in the refrigerant piping to the outdoor unit matches authentication information uniquely corresponding to the air conditioner or an authorized operator; determining whether pump-down is authorized based on the determination result; and setting pump-down as executable if it is determined that pump-down is authorized.

[0126] According to this method, pump-down can be set so that only authorized workers such as specialists can perform pump-down, thereby improving the safety of pump-down. In addition, whether or not pump-down can be performed can be set based on the judgment result received from the authentication server or the information terminal of the worker.

[0127] (Technology 15) A computer program for causing an air conditioner to execute the pump-down management method according to Technology 13 or Technology 14.

[0128] According to this computer program, the air conditioner can be caused to execute a pump-down management method, and pump-down can be set so that only authorized workers, such as specialists, can perform pump-down, thereby improving the safety of pump-down.

[0129] (Technology 16) A non-transitory computer-readable storage medium having a computer program stored therein, the non-transitory computer-readable storage medium realizing the pump-down management method described in Technology 13 or Technology 14 when the computer program is executed by a processor.

[0130] This storage medium makes it possible to cause the air conditioner to execute the pump-down management method, and to set it so that pump-down can be performed only by authorized operators, such as specialists, thereby improving the safety of pump-down.

[0131] The above are merely specific embodiments of the present disclosure, and the scope of protection of the present disclosure is not limited thereto. The present disclosure includes the contents described above in the drawings and the specific embodiments described above, but the present disclosure is not limited thereto. Various disclosed embodiments or examples can be combined without departing from the scope or spirit of the present disclosure. Modifications that do not depart from the functional and structural principles of the present disclosure are within the scope of the claims. [Explanation of symbols]

[0132] 1. Air conditioner 10 Indoor unit 102 Indoor heat exchanger 104 Indoor Fan 12 Outdoor unit 122 Outdoor heat exchanger 124 Outdoor fan 126 Compressor 128 Expansion valve 129 Four-way valve 14 Storage section 16 Control section 18 Communications Department 20 Input section 22 Refrigerant piping 24 Liquid side valve 26 Gas side valve 28 Refrigerant pressure sensor 28A 1st refrigerant pressure sensor 28B Second refrigerant pressure sensor 30 Protective cover 32 Open / close sensor 50 Authentication Server 60 Terminal Equipment 62 Related Applications 70 External sources SC1~SC3 screen

Claims

1. It is an air conditioner, Indoor unit and Outdoor unit and A refrigerant pipe connecting the indoor unit and the outdoor unit, through which a flammable refrigerant flows, Control unit and Includes, The control unit, Input information is obtained to authorize a pump-down to recover the flammable refrigerant in the refrigerant piping to the outdoor unit. Based on the input information, it is determined whether or not pump-down is permitted. If it is determined that a pump-down is permitted, set the pump-down to be executable. Air conditioner.

2. The air conditioner further includes a liquid-side valve provided in the refrigerant piping for controlling the flow of the flammable refrigerant, The control unit, If it is detected that the liquid-side valve is closed, the pump-down operation will be disabled until it is determined that pump-down is permitted. The air conditioner according to claim 1.

3. The outdoor unit includes an expansion valve provided in the refrigerant piping, The air conditioner further includes a refrigerant pressure sensor, The refrigerant pressure sensor is provided in the refrigerant piping between the expansion valve and the liquid side valve, and detects the refrigerant pressure of the flammable refrigerant flowing through the refrigerant piping. The control unit determines whether to open or close the liquid-side valve based on the refrigerant pressure detected by the refrigerant pressure sensor. The air conditioner according to claim 2.

4. The indoor unit includes an indoor heat exchanger. The outdoor unit includes an expansion valve provided in the refrigerant piping, The air conditioner further includes a first refrigerant pressure sensor and a second refrigerant pressure sensor for detecting the refrigerant pressure of the flammable refrigerant flowing through the refrigerant piping, The first refrigerant pressure sensor is provided in the refrigerant piping between the expansion valve and the liquid side valve, The second refrigerant pressure sensor is provided in the refrigerant piping between the liquid side valve and the indoor heat exchanger. The control unit determines whether to open or close the liquid-side valve based on the pressure difference between the refrigerant pressure detected by the first refrigerant pressure sensor and the refrigerant pressure detected by the second refrigerant pressure sensor. The air conditioner according to claim 2.

5. The aforementioned air conditioner is A liquid-side valve provided in the refrigerant piping for controlling the flow of the flammable refrigerant, A protective cover covering the liquid side valve, An opening / closing sensor for detecting the opening and closing of the protective cover, It further includes, When the control unit detects that the protective cover is open by the opening / closing sensor, it sets the pump-down to be disabled until it determines that pump-down is permitted. The air conditioner according to claim 1.

6. The outdoor unit further includes a compressor connected to the refrigerant piping, The control unit sets the pump-down operation impossible by keeping the compressor in a stopped state. The air conditioner according to claim 1.

7. The control unit sets the pump-down function to be disabled by maintaining the liquid-side valve in an open state. The air conditioner according to claim 2.

8. If the control unit determines that pump-down is permitted, it sets the available time for pump-down to be performed. The air conditioner according to claim 1.

9. If the control unit determines that pump-down is not permitted, or sets pump-down to be disabled, it will output information indicating that pump-down is disabled to the air conditioner or a terminal device associated with the air conditioner. The air conditioner according to claim 1.

10. The aforementioned air conditioner is An input unit or a communication unit that acquires the aforementioned input information, A storage unit that stores first authentication information uniquely corresponding to the air conditioner, It further includes, The control unit determines that pump-down is permitted if it determines that the input information matches the first authentication information. The air conditioner according to claim 1.

11. The aforementioned air conditioner further includes a communication unit, The control unit, The communication unit or the input unit of the air conditioner acquires the input information, The communication unit transmits the input information to the authentication server. The communication unit receives from the authentication server a determination result regarding whether the input information matches the second authentication information that uniquely corresponds to an authorized worker. Based on the above judgment result, it is determined whether or not pump-down is permitted. The air conditioner according to claim 1.

12. It is an air conditioner, Indoor unit and Outdoor unit and A refrigerant pipe connecting the indoor unit and the outdoor unit, through which a flammable refrigerant flows, Control unit and Includes, The control unit, The system obtains a determination result regarding whether the input information for authorizing a pump-down to recover the flammable refrigerant in the refrigerant piping to the outdoor unit matches the authentication information uniquely corresponding to the air conditioner or authorized worker. Based on the above judgment result, determine whether or not pump-down is permitted. If it is determined that a pump-down is permitted, set the pump-down to be executable. Air conditioner.

13. A method for managing the pump-down of an air conditioner, The aforementioned air conditioner is Indoor unit and Outdoor unit and A refrigerant pipe connecting the indoor unit and the outdoor unit, through which a flammable refrigerant flows, Includes, The aforementioned pump-down management method is: The steps include obtaining input information for authorizing a pump-down to recover the flammable refrigerant in the refrigerant piping to the outdoor unit, The steps include determining whether pump-down is permitted based on the input information, If it is determined that a pump-down is permitted, the steps include: setting the pump-down to be executable, including, Method for managing the pump-down process of an air conditioner.

14. A method for managing the pump-down of an air conditioner, The aforementioned air conditioner is Indoor unit and Outdoor unit and A refrigerant pipe connecting the indoor unit and the outdoor unit, through which a flammable refrigerant flows, Includes, The aforementioned pump-down management method is: The steps include obtaining a determination result regarding whether the input information for authorizing a pump-down to recover the flammable refrigerant in the refrigerant piping to the outdoor unit matches authentication information uniquely corresponding to the air conditioner or an authorized worker, Based on the aforementioned judgment result, a step is to determine whether or not pump-down is permitted, If it is determined that a pump-down is permitted, the steps include: setting the pump-down to be executable, including, Method for managing the pump-down process of an air conditioner.

15. A computer program for causing an air conditioner to perform the pump-down management method described in claim 13 or 14.

16. A non-temporary, computer-readable storage medium on which computer programs are stored, When the computer program is executed by the processor, the pump-down management method described in claim 13 or 14 is realized. A non-temporary, computer-readable storage medium.

Images